Jump to content

Replacement Tweeter for the K-77 Done!!


BEC

Recommended Posts

I have been working on this literally for years. I knew there had to be something better than the K-77.

My first effort was a duplicate of the K-77 with interior improvements as an attempt to eliminate some of its problems. The result was this tweeter pictured below. It is technically better built but sounds just like a K-77 and tests almost the same.

post-9312-13819283676112_thumb.jpg

Link to comment
Share on other sites

  • Replies 156
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Posted Images

Second effort was a massive magnet model of the same thing. This thing looks impressive and tests a bit better than the single magnet model, but not enough improvement to be worth the effort.

Bob Crites

post-9312-13819283676832_thumb.jpg

Link to comment
Share on other sites

Up to present time. Here is one of the prototypes of the new tweeter using the Eminence APT-50 driver with a cobbled together adapter and modified K-77 horn. Several forum members have been listening to these for months now. This thing really sings! People were pleased enough with it to convince me to spend the money to have a custom horn molded.

Bob Crites

post-9312-13819283677472_thumb.jpg

Link to comment
Share on other sites

Bill,

Yes, the horn screws on the driver. That will also allow people building their own motor boards to use a router to make a 1/8 inch recess in the front of the motor board to flush mount the tweeter without Z-brackets.

Bob Crites

Link to comment
Share on other sites

Guys,

I think Bob has got a good thing going with those new tweeters. I beleive that horn is a diffraction type that will yield better dispersion BELOW 6000 Hz when mounted vertically. At 6000 Hz and above I don't think it matters which way you mount it. I think that new driver will allow a lower crossover letting you take advantage of vertical mounting. The K400 and K500 squawker horns are not very good and I think crossing over to the tweeter lower would be an improvement. The total mod would require a redesigned crossover with a transition at about 4500 Hz and turning the new horn vertical. If you really want to stick to the K400 or K500 horns, I think this is the way to go. Right now, I do not offer a 4500 Hz netwrok, but I could easily develop an ES4500 to pair with one of my AP12 sereis networks for this application. Moding the stock Klipsch networks down to a 4500 Hz cross isn't possible because of the lack of a high frequency limit filter on the squawker. The K55 goes up to 6000 Hz like it or not!

Al K.

Link to comment
Share on other sites

"Modding the stock Klipsch networks down to a 4500 Hz cross isn't possible because of the lack of a high frequency limit filter on the squawker. The K55 goes up to 6000 Hz like it or not!"

Not entirely correct Master Yoda. I've been bandpassing the squawker on the old filters for well over a year now, and Bob started playing with it himself after he realized the full potential of the tweeter -- just a single .50mH inductor between the squawker and the autoformer works good enough. Not the optimized beauties you offer -- but it sounds pretty darn good. Yeah, yeah -- first order filters are sloppy and crude. I'll post some pics tomorrow of the network I'm running right now -- you better break out the Pepto.:)

Congratulations Bob, and thank you as well on behalf of Klipsch Heritage listeners everywhere!

Link to comment
Share on other sites

Dean,

Yep, you can jurey rig a 4500 Hz lowpass into the squawker of a stock Klipsch network. It is doable, but it will not be a good network! When I say it is impossible I mean it is not advisable for a lot of reasons. The least of which is that even if you do the 4500Hz lowpass correctly, at a 13 Ohm level, the rest of the long list of compromises of the stock network remain. Do it right!

As to the horn mounting, I think it's always best to mount any driver flush with the baffle board. It can even mess up a woofer to mount it from the back. I have seen that in the text books. I think it's even more important for a tweeter. That is why Klipsch went to the "Z bracket" monting.

Al K.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...